Measurement of Plasma Ammonia Is Affected in Patients Receiving Asparaginase Therapy

[摘要] We recently observed a progressive increase in plasma ammonia concentrations in specimens from two patients that were being reanalyzed to confirm critical action value events (≥100 μmol/L). The initial analysis in one patient revealed an ammonia concentration of 163 μmol/L (Hitachi 917; Roche Diagnostics). Analyses at successive 20-min intervals revealed concentrations of 235, 292, and 315 μmol/L, respectively. Similarly, in another patient, the plasma ammonia concentrations were 209, 272, 351, and 383 μmol/L for the original and repeat measurements, respectively. Both patients’ medical records indicated that they were receiving antineoplastic therapy with asparaginase (ASNase).The primary proteolytic activity of ASNase is the conversion of the amino acid asparagine to aspartic acid and ammonia. ASNase is also responsible for the turnover of …

[学科分类] 过敏症与临床免疫学